BEIJING —
China will set up a new "state security committee'' as it seeks to tackle growing social unrest and unify the powers of a disparate security apparatus in the face of growing challenges at home and abroad, the government said on Tuesday.

Details of how the committee will work and when exactly it will begin operations were left unclear in the announcement, carried by state news agency Xinhua at the end of a key meeting of the ruling Communist Party to map out political and economic reforms.

Xinhua said the committee would "improve the system of national security and the country's national security strategy'' so as to "effectively prevent and end social disputes and improve public security."

Cheng Li, a fellow at the Brookings Institution in Washington and an expert on Chinese politics, said the idea was based on the National Security Council in the United States and would increase coordination between the various wings of China's security bureaucracy, split now between the police, military, intelligence and diplomatic services.

"The official line is to better coordinate the very different domains: the intelligence, military, foreign policy, public security and also national defence. This gives tremendous power to the presidency,'' Cheng said, referring to President Xi Jinping.

China's potential flashpoints overseas include North Korea and the South China Sea, where the potential exists for a crisis to escalate quickly.

For years, officials have argued for a national security agency "that can handle crises in a more effective manner," said David Zweig, a political scientist at the Hong Kong University of Science and Technology.

"This could be a positive thing, in the sense that it would be a way for all the people involved in a foreign policy crisis to be in the same room at the same time,'' Zweig said.

The new committee could also strengthen the powers of the domestic security apparatus, grappling with rising numbers of protests over pollution, illegal land grabs and corruption, as well as continued unrest in places like Tibet and Xinjiang.

"I think what it says is that China, the party and government expect a considerable rise in social tensions over the next few years,'' said Nicholas Bequelin, senior Asia researcher for New York-based Human Rights Watch.

"Since legal reform and establishing rule of law is on the back burner at the moment...we can expect that the party and the government will try to respond to this potential risk by other means.''

Critics say Xi's administration has presided over a harsh crackdown that has moved beyond the targeting of dissidents demanding political change, including detaining activists who have called for officials to publicly disclose their wealth.

The Xinhua communique did refer to "upholding the constitution and laws'' and "improving judicial practice," but one prominent dissident said he feared things would only get worse with the new security committee.

"It will be used against rights defenders, people who uphold universal values, supporters of free speech and freedom of religion, people who are organising protests - all those the Chinese government cannot tolerate as they seem them as a threat to their rule,'' Hu Jia told Reuters.

"The Soviet Union had a state security committee - it was called the KGB. Twenty years after the fall of the Soviet Union, China is resurrecting this. It's a step backwards into history.''